Monday 9/27 8:45 am
Last night (and in the overnight hours), showers developed across the forecast area. The showers mainly favored the southern portions of the forecast area. Most areas recorded 0.10″ or less. Eastern portions of La Plata County recorded up to 0.30″. Archuleta County was the big winner with several reports between 0.30″ and 0.40″ This was more than I expected, so it was a good start for what still looks to be a wet week.
Expect storms to fire up again this afternoon. High-resolution models are showing very high CAPE values (available energy for thunderstorm development) this afternoon. Showers should continue on and off throughout the evening and possibly overnight hours.
Here are the CAPE values through 9 pm tonight.
Let’s start off with our current rainmaker. This is a nice animated satellite view that shows the classic counterclockwise flow around the area of low pressure.
This feature will begin to interact with a large trough and an associated area of low pressure which is about to come onshore across the Pacific Northwest.
If it looks a bit like a hurricane, there is a reason. It is difficult to see but that low pressure is 981 MB (millibars)! For comparison, this year we have had 19 named tropical features, only 4 of the 19 were stronger than this low-pressure system.
As it approaches it will draw in the feature that is to our south. What happens after that is still up for debate. The models are still diverging after Wednesday. The Euro shows various leftovers that will keep showers going through the weekend, then another system coming in leading to 10 days of precipitation.
The GFS hurries the system out on Thursday and keeps the forecast mainly dry until next week when another system arrives. Here is what that looks like. Remember, green is rain, blue is snow, pink is ice. The darker the shades the heavier the precipitation. These are 6-hour increments, so there are 4 frames per day.
GFS notice how quickly the precipitation leaves before returning next week.
Compare that to the Euro that shows some precipitation nearly every day.
All said and done here are the 10-day precipitation totals.
My next update will be Tuesday. Thanks for following and supporting the site!